JP6776511B2 - Manufacturing method of composite container, composite preform and composite container - Google Patents

Description

The present invention relates to a method for producing a composite container, a composite preform and a composite container.

Recently, plastic bottles have become common as bottles for containing the contents of foods and drinks, and such plastic bottles contain the contents.

A plastic bottle containing such a content liquid is manufactured by inserting a preform into a mold and biaxially stretching blow molding.

By the way, in the conventional biaxial stretching blow molding method, a container shape is formed by using a preform containing, for example, a single layer material such as PET or PP, a multilayer material or a blend material. However, in the conventional biaxial stretching blow molding method, it is general that the preform is simply molded into a container shape. Therefore, when the container is to have various functions and properties (barrier property, heat retention property, etc.), the means thereof is limited, for example, changing the material constituting the preform.

Japanese Unexamined Patent Publication No. 2009-241526

The present invention has been made in consideration of such a point, and is capable of producing a composite container having various functions and characteristics such as gas barrier properties with high quality. It is intended to provide preforms and composite containers.

The present invention comprises a step of preparing a preform made of a plastic material while having a mouth portion, a body portion, and a bottom portion in a method of manufacturing a composite container, and a step of providing a plastic member on the outside of the preform. By performing blow molding on the preform and the plastic member using a blow molding mold, the preform and the plastic member are integrally expanded to form a container body corresponding to the preform. A step of manufacturing a composite container having a plastic member provided in close contact with the outside of the container body is provided, and in the step of manufacturing the composite container, the lateral stretching ratio of the preform with respect to the container body is determined. It is a method for manufacturing a composite container, which is characterized by having a thickness of 3.5 times or less.

The present invention is a method for manufacturing a composite container, characterized in that the maximum thickness of the body of the preform is 2 mm to 10 mm.

The present invention is a method for manufacturing a composite container, characterized in that the maximum thickness of the plastic member before blow molding is 0.1 mm to 2 mm.

The present invention is a composite preform characterized by being used in the method for producing the composite container.

The present invention is a composite preform characterized in that the maximum thickness of the body portion of the preform is 2 mm to 10 mm.

The present invention is a composite preform characterized in that the maximum thickness of the plastic member is 0.1 mm to 2 mm.

The present invention is a composite container, characterized in that it is manufactured by the method for producing the composite container.

According to the present invention, it is possible to prevent a problem that the plastic member is broken when the composite container is manufactured, so that the composite container to which various functions and characteristics such as gas barrier properties are imparted can be produced with high quality. Can be made.

FIG. 1 is a partial vertical sectional view showing a composite container according to the first embodiment of the present invention. FIG. 2 is a horizontal sectional view (FIG. II-II sectional view of FIG. 1) showing a composite container according to the first embodiment of the present invention. FIG. 3 is a partial vertical sectional view showing a composite preform according to the first embodiment of the present invention. 4 (a) to 4 (d) are perspective views showing various plastic members. 5 (a) to 5 (f) are schematic views showing a method for manufacturing a composite container according to the first embodiment of the present invention. 6 (a) to 6 (f) are schematic views showing a method of manufacturing a composite container according to a modified example of the first embodiment of the present invention. 7 (a) to 7 (g) are schematic views showing a method of manufacturing a composite container according to a modified example of the first embodiment of the present invention. FIG. 8 is a partial vertical sectional view showing a modified example of the composite container according to the first embodiment of the present invention. FIG. 9 is a partial vertical sectional view showing a modified example of the composite preform according to the first embodiment of the present invention. FIG. 10 is a partial vertical sectional view showing a composite container according to a second embodiment of the present invention. FIG. 11 is a horizontal cross-sectional view (XI-XI line cross-sectional view of FIG. 10) showing a composite container according to a second embodiment of the present invention. FIG. 12 is a partial vertical sectional view showing a composite preform according to a second embodiment of the present invention. 13 (a) to 13 (f) are schematic views showing a method for manufacturing a composite container according to a second embodiment of the present invention. 14 (a) to 14 (f) are schematic views showing a method of manufacturing a composite container according to a modified example of the second embodiment of the present invention. 15 (a) to 15 (g) are schematic views showing a method of manufacturing a composite container according to a modified example of the second embodiment of the present invention. FIG. 16 is a partial vertical sectional view showing a modified example of the composite container according to the second embodiment of the present invention. FIG. 17 is a partial vertical sectional view showing a modified example of the composite preform according to the second embodiment of the present invention.

First Embodiment Hereinafter, the first embodiment of the present invention will be described with reference to the drawings. 1 to 9 are diagrams showing the first embodiment of the present invention.

First, with reference to FIGS. 1 and 2, the outline of the composite container produced by the method for manufacturing a composite container (blow molding method) according to the present embodiment will be described. In addition, in this specification, "upper" and "lower" mean the upper part and the lower part in the state (FIG. 1) in which the composite container 10A is upright, respectively.

As will be described later, the composite container 10A shown in FIGS. 1 and 2 is biaxially stretched with respect to the composite preform 70 (see FIG. 3) including the preform 10a and the plastic member 40a using a blow molding die 50. It is obtained by integrally expanding the preform 10a of the composite preform 70 and the plastic member 40a by performing blow molding.

Such a composite container 10A includes a container body 10 made of a plastic material located inside and a plastic member 40 provided in close contact with the outside of the container body 10.

Of these, the container body 10 includes a mouth portion 11, a neck portion 13 provided below the mouth portion 11, a shoulder portion 12 provided below the neck portion 13, a body portion 20 provided below the shoulder portion 12, and a body. A bottom portion 30 provided below the portion 20 is provided.

On the other hand, the plastic member 40 is in close contact with the outer surface of the container body 10 in a thinly extended state, and is attached to the container body 10 in a state where it does not easily move or rotate.

Next, the container body 10 will be described in detail. As described above, the container body 10 has a mouth portion 11, a neck portion 13, a shoulder portion 12, a body portion 20, and a bottom portion 30.

Of these, the mouth portion 11 has a screw portion 14 screwed to a cap (not shown) and a flange portion 17 provided below the screw portion 14. The shape of the mouth portion 11 may be a conventionally known shape.

The neck portion 13 is located between the flange portion 17 and the shoulder portion 12, and has a substantially cylindrical shape having a substantially uniform diameter. Further, the shoulder portion 12 is located between the neck portion 13 and the body portion 20, and has a shape in which the diameter gradually increases from the neck portion 13 side to the body portion 20 side.

Further, the body portion 20 has a cylindrical shape having a substantially uniform diameter as a whole. However, the present invention is not limited to this, and the body portion 20 may have a polygonal tubular shape such as a quadrangular tubular shape or an octagonal tubular shape. Alternatively, the body portion 20 may have a tubular shape having a non-uniform horizontal cross section from the upper side to the lower side. Further, in the present embodiment, the body portion 20 is not formed with irregularities and has a substantially flat surface, but the present invention is not limited to this. For example, the body portion 20 may have irregularities such as a panel or a groove.

On the other hand, the bottom portion 30 has a recess 31 located at the center and a ground contact portion 32 provided around the recess 31. The shape of the bottom portion 30 is not particularly limited, and may have a conventionally known bottom shape (for example, a petaloid bottom shape, a round bottom shape, or the like).

The thickness T ₁ of the container body 10 in the body 20 is not limited to this, but for example, in the case of a large bottle having a full filling capacity of 3 L or more, it means 300 μm to 500 μm (300 μm or more and 500 μm or less). Similarly, the weight of the container body 10 can be as thin as 75 g to 200 g, though not limited to this. By reducing the wall thickness of the container body 10 in this way, the weight of the container body 10 can be reduced. In the case of a small bottle having a full filling capacity of less than 3 L, the thickness T ₁ of the container body 10 can be reduced to about 100 μm to 200 μm, and the weight of the container body 10 is not limited to this. Although not, it can be 10 g to 20 g. By reducing the wall thickness of the container body 10 in this way, the weight of the container body 10 can be reduced.

Such a container body 10 can be manufactured by biaxially stretching blow molding a preform 10a (described later) manufactured by injection molding a synthetic resin material. As the material of the preform 10a, that is, the container body 10, a thermoplastic resin, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), and PC (polycarbonate) can be used. preferable. The container body 10 may be colored in colors such as red, blue, yellow, green, brown, black, and white, but is preferably colorless and transparent in consideration of ease of recycling. Further, the above-mentioned various resins may be blended and used. Further, a thin-film film such as a diamond-like carbon film or a silicon oxide thin film may be formed on the inner surface of the container body 10 in order to enhance the barrier property of the container.

Further, the container body 10 can be formed as a multi-layer molded bottle having two or more layers. That is, by extrusion molding or injection molding, for example, the intermediate layer is provided with gas barrier properties such as MXD6, MXD6 + fatty acid salt, PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer) or PEN (polyethylene naphthalate) and light-shielding properties. As the resin (intermediate layer) to have, a preform 10a composed of three or more layers may be extruded and then blow-molded to form a multi-layer bottle having gas barrier properties and light-shielding properties. As the intermediate layer, a resin blended with the above-mentioned various resins may be used.

Further, by mixing an inert gas (nitrogen gas, argon gas) with the melt of the thermoplastic resin, a foam preform having a foam cell diameter of 0.5 to 100 μm is formed, and this foam preform is blow molded. By doing so, the container body 10 may be manufactured. Since such a container body 10 has a foam cell built-in, the light-shielding property of the entire container body 10 can be improved.

In the case of a large bottle, the container body 10 is preferably a bottle having a full filling capacity of 3000 ml to 50,000 ml, and more preferably a full filling capacity of 3000 ml to 20000 ml. In the case of a small bottle, the full filling capacity is preferably 100 ml to 3000 ml, and more preferably the full filling capacity is 200 ml to 2000 ml.

Further, in the case of a large bottle, the height H ₁ from the lower side of the flange portion 17 of the container body 10 to the ground contact portion 32 is preferably 200 mm to 1000 mm, and the height H ₂ of the mouth portion 11 is, for example, 10 mm to. It is preferably 100 mm. Further, the maximum width (maximum diameter) D ₁ of the body 20 of the container body 10 is preferably 75 mm to 600 mm. In the case of a small bottle, the height H ₁ from the lower side of the flange portion 17 of the container body 10 to the ground contact portion 32 is preferably 50 mm to 200 mm, and the height H ₂ of the mouth portion 11 is, for example, 7 mm to 30 mm. It is preferable to do so. Further, the maximum width (maximum diameter) D ₁ of the body 20 of the container body 10 is preferably 40 mm to 100 mm.

Next, the plastic member 40 will be described. The plastic member 40 (40a) is provided so as to surround the outside of the preform 10a as described later, and is obtained by being brought into close contact with the outside of the preform 10a and then biaxially stretched and blow-molded together with the preform 10a. It is a thing. As will be described later, the plastic member 40 is manufactured by stretching the plastic member 40a together with the preform 10a.

The plastic member 40 is attached to the outer surface of the container body 10 without being adhered, and is in close contact with the container body 10 so as not to move or rotate. The plastic member 40 is thinly stretched on the outer surface of the container body 10 to cover the container body 10. Further, as shown in FIG. 2, the plastic member 40 is provided over the entire circumferential direction so as to surround the container body 10, and has a substantially circular horizontal cross section.

In this case, the plastic member 40 is provided so as to cover the shoulder portion 12, the body portion 20, and the bottom portion 30 of the container body 10, excluding the mouth portion 11 and the neck portion 13. As a result, desired functions and characteristics can be imparted to the shoulder portion 12, the body portion 20, and the bottom portion 30 of the container body 10.

The plastic member 40 may be provided in the entire area or a part of the container body 10 other than the mouth portion 11. For example, the plastic member 40 may be provided so as to cover the entire neck portion 13, shoulder portion 12, body portion 20, and bottom portion 30 of the container body 10 except for the mouth portion 11. Further, the number of the plastic member 40 is not limited to one, and a plurality of plastic members 40 may be provided. For example, two plastic members 40 may be provided on the outer surface of the shoulder portion 12 and the outer surface of the bottom portion 30, respectively.

On the other hand, since the plastic member 40 is not welded or adhered to the container body 10, it can be peeled off from the container body 10 and removed. Specifically, for example, the plastic member 40 may be cut off using a knife or the like, or the plastic member 40 may be provided with a cutting line (not shown in advance) and the plastic member 40 may be peeled off along the cutting line. it can. As a result, the plastic member 40 can be separated and removed from the container body 10.

Such a plastic member 40 may not have a contracting action on the preform 10a, or may have a shrinking action.

The thickness T ₂ of the plastic member 40 is not limited to this, but can be, for example, about 100 μm to 3000 μm in a state of being attached to the container body 10.

In the present embodiment, the plastic member 40 may be colored in a visible light color such as red, blue, yellow, green, brown, black, and white. Further, the plastic member 40 may be (semi) transparent or opaque. In this case, for example, the plastic member 40 may be colored in a visible light color, and the container body 10 may be colorless and transparent. Alternatively, both the container body 10 and the plastic member 40 may be colored in visible light color. When the plastic member 40 colored in visible light color is produced, a visible light color pigment may be added to the molding material in the step of producing the plastic member 40a before blow molding by injection molding or the like. ..

Next, the configuration of the composite preform according to the present embodiment will be described with reference to FIG.

As shown in FIG. 3, the composite preform 70 includes a preform 10a made of a plastic material and a bottomed cylindrical plastic member 40a provided on the outside of the preform 10a.

The preform 10a includes a mouth portion 11a, a body portion 20a connected to the mouth portion 11a, and a bottom portion 30a connected to the body portion 20a. Of these, the mouth portion 11a corresponds to the mouth portion 11 of the container body 10 described above, and has substantially the same shape as the mouth portion 11. Further, the body portion 20a corresponds to the neck portion 13, the shoulder portion 12 and the body portion 20 of the container body 10 described above, and has a substantially cylindrical shape. The bottom portion 30a corresponds to the bottom portion 30 of the container body 10 described above, and has a substantially hemispherical shape.

In the present embodiment, in the case of a large bottle, the diameter d ₁ of the body portion 20a is 50 mm to 200 mm, preferably 50 mm to 100 mm. In the case of a small bottle, the diameter d ₁ of the body portion 20a is 25 mm to 50 mm, preferably 25 mm to 35 mm. When the preform 10a is manufactured by injection molding, the body diameter of the body portion 20a may be slightly smaller on the bottom portion 30a side than on the mouth portion 11a side in order to provide a draft that makes it easy to remove from the mold. .. In this case, the diameter d ₁ is defined by the diameter at the thickest part of the body portion 20a. By the way, in the case of a large bottle, the diameter of the body of a conventional general preform is about 50 mm to 100 mm. On the other hand, according to the present embodiment, the diameter d ₁ of the body portion 20a is thickened to 100 mm or more. Therefore, as will be described later, in the step of producing the composite container 10A by blow molding, the preform with respect to the container body 10 is performed. The lateral stretching ratio of 10a can be 3.5 times or less. In the case of a small bottle, the diameter of the body of a conventional general preform is about 20 mm to 25 mm. On the other hand, according to the present embodiment, the diameter d ₁ of the body portion 20a is thickened to 25 mm or more. Therefore, as will be described later, in the step of producing the composite container 10A by blow molding, the preform with respect to the container body 10 is performed. The lateral stretching ratio of 10a can be 3.5 times or less. This makes it possible to prevent the plastic member 40a from being overextended and broken.

Further, the height h ₁ from the lower side of the flange portion 17 of the preform 10a to the lowest point of the bottom portion 30a is preferably 200 mm to 1000 mm, more preferably 200 mm to 600 mm in the case of a large bottle. In the case of a small bottle, it is preferably 50 mm to 200 mm, and more preferably 100 mm to 200 mm. By setting the height h ₁ to this range, it is possible to suppress longitudinal stretching and facilitate molding. The height h ₂ of the mouth portion 11a of the preform 10a is substantially the same as the height H ₂ of the mouth portion 11 of the container body 10 described above. For example, in the case of a large bottle, it is 10 mm to 100 mm, and a small bottle. In the case of, it is 7 mm to 30 mm.

Further, the maximum thickness t ₁ of the preform 10a in the body portion 20a is preferably 4 mm to 10 mm, more preferably 6 mm to 8 mm in the case of a large bottle. By setting the thickness t ₁ to 4 mm or more, it is possible to easily adjust the wall thickness of the container body 10. Further, by setting the thickness t ₁ to 10 mm or less, the thickness T ₁ of the container body 10 becomes too thick even when the lateral stretching ratio of the preform 10a with respect to the container body 10 is 3.5 times or less. Can be prevented. In the case of a small bottle, it is preferably 2 mm to 5 mm, and more preferably 3 mm to 4.5 mm. By setting the thickness t ₁ to 3 mm or more, it is possible to easily adjust the wall thickness of the container body 10. Further, by setting the thickness t ₁ to 5 mm or less, the thickness T ₁ of the container body 10 becomes too thick even when the lateral stretching ratio of the preform 10a with respect to the container body 10 is 3.5 times or less. Can be prevented.

The plastic member 40a is attached to the outer surface of the preform 10a without being adhered to the preform 10a so that it does not move or rotate, or is in close contact with the preform 10a so as not to fall under its own weight. .. The plastic member 40a is provided over the entire circumferential direction so as to surround the preform 10a, and has a circular horizontal cross section.

The thickness t ₂ of the plastic member 40a can be, for example, about 100 μm to 3000 μm. By setting the thickness t ₂ to 100 mm or more, it is possible to prevent a problem that the plastic member 40a is stretched and broken during blow molding. Further, by setting the thickness t ₂ to 3000 mm or less, it is possible to prevent a problem that the plastic member 40a is not sufficiently stretched during blow molding.

In this case, the plastic member 40a is provided so as to cover the entire body portion 20a except for the portion 13a corresponding to the neck portion 13 of the container body 10 and the entire bottom portion 30a. Further, the plastic member 40a may be colored in a visible light color such as red, blue, yellow, green, brown, black, and white.

The plastic member 40a may be provided in the entire area or a part of the area other than the mouth portion 11a. For example, the plastic member 40a may be provided so as to cover the entire body portion 20a and the bottom portion 30a except for the mouth portion 11a. Further, the number of plastic members 40a is not limited to one, and a plurality of plastic members 40a may be provided. For example, two plastic members 40a may be provided at two locations on the outer side of the body portion 20a, respectively.

Such a plastic member 40a may not have an action of contracting with respect to the preform 10a, or may have an action of contracting.

In the former case, the plastic member 40a is manufactured by, for example, a direct blow molding tube manufactured by a direct blow molding method, a sheet molding tube manufactured by a sheet molding method, an extrusion tube manufactured by extrusion molding, or inflation molding. An inflation molding tube or the like can be used, but the present invention is not limited to this, and a molding method other than the above may be used.

In the latter case, that is, when the plastic member (outer shrinking member) 40a has an action of contracting, the plastic member (outer shrinking member) 40a is, for example, when an external action (for example, heat) is applied. Those that shrink (for example, heat shrink) with respect to the reform 10a may be used. Alternatively, the plastic member (outer contractile member) 40a may itself have contractility or elasticity and can be contracted without applying an external action.

Examples of the plastic member 40a include polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, poly-4-methylpentene-1, polystyrene, AS resin, ABS tree, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, and the like. Polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, diallyl phthalate resin, fluororesin, polymethyl methacrylate, polyacrylic acid, methyl polyacrylic acid, polyacrylonitrile, polyacrylamide, polybutadiene, polybutene-1, polyisoprene, polychloroprene, Ethylenepropylene rubber, butyl rubber, nitrile rubber, acrylic rubber, silicone rubber, fluororubber, nylon 6, nylon 6,6, nylon MXD6, aromatic polyamide, polycarbonate, ethylene polyterephthalate, butylene polyterephthalate, ethylene polynaphthalate, U polymer, liquid crystal polymer, modified polyphenylene ether, polyetherketone, polyetheretherketone, unsaturated polyester, alkyd resin, polyimide, polysulfone, polyphenylene sulfide, polyethersulfone, silicone resin, polyurethane, phenol resin, urea resin, polyethylene oxide , Polyetherketone, polyacetal, epoxy resin and the like. Of these, it is preferable to use a thermoplastic inelastic resin such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). Further, they may be a blended material, a multi-layer structure, or a partial multi-layer structure. Further, various additives may be added to the material of the plastic member 40a in addition to the resin as the main component as long as the characteristics are not impaired. Additives include, for example, plasticizers, UV stabilizers, anticolorants, matting agents, deodorants, flame retardants, weatherproofing agents, antistatic agents, thread friction reducing agents, slip agents, mold release agents, anti-corrosion agents. Oxidizing agents, ion exchangers, coloring pigments and the like can be added. In addition, by mixing an inert gas (nitrogen gas, argon gas) with the melt of the thermoplastic resin, a foam member having a foam cell diameter of 0.5 to 100 μm is used, and this foam preform is molded. , The light blocking effect can be enhanced.

Further, the plastic member 40a may be made of the same material as the container body 10 (preform 10a). In this case, the plastic member 40 can be arranged mainly in the portion of the composite container 10A where the strength is desired to be increased, and the strength of the portion can be selectively increased. For example, the plastic member 40 may be provided around the shoulder portion 12 and the bottom portion 30 of the container body 10 to increase the strength of this portion. Examples of such a material include thermoplastic resins, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), and PC (polycarbonate).

Further, the plastic member 40a may be made of a material having a gas barrier property such as an oxygen barrier property or a water vapor barrier property. In this case, it is possible to improve the gas barrier property of the composite container 10A and prevent the content liquid from being deteriorated by oxygen or water vapor without using a multilayer preform or a preform containing a blend material as the preform 10a. For example, the plastic member 40 may be provided over the entire area of the shoulder portion 12, the neck portion 13, the body portion 20, and the bottom portion 30 of the container main body 10 to enhance the gas barrier property of this portion. Examples of such a material include PE (polyethylene), PP (polypropylene), MXD-6 (nylon), PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer), or oxygen such as a fatty acid salt in these materials. It is also possible to mix an absorbent material.

Further, the plastic member 40a may be made of a material having a light ray barrier property such as ultraviolet rays. In this case, it is possible to enhance the light barrier property of the composite container 10A and prevent the content liquid from being deteriorated by ultraviolet rays or the like without using a multilayer preform or a preform containing a blend material as the preform 10a. For example, in the container main body 10, a plastic member 40a may be provided over the entire area of the shoulder portion 12, the neck portion 13, the body portion 20, and the bottom portion 30 to enhance the ultraviolet barrier property of this portion. As such a material, a blended material or a material obtained by adding a light-shielding resin to PET, PE, or PP can be considered. Further, a foaming member having a foam cell diameter of 0.5 to 100 μm, which is produced by mixing an inert gas (nitrogen gas, argon gas) with the melt of the thermoplastic resin, may be used.

Further, the plastic member 40a may be made of a material (material having low thermal conductivity) having higher cold retention or heat retention than the plastic material constituting the container body 10 (preform 10a). In this case, it is possible to make it difficult for the temperature of the content liquid to be transmitted to the surface of the composite container 10A without increasing the thickness of the container body 10 itself. As a result, the cold insulation property or the heat insulation property of the composite container 10A is enhanced. For example, the plastic member 40 may be provided on all or part of the body 20 of the container body 10 to improve the cold or heat retention of the body 20. Further, when the user grips the composite container 10A, it is prevented that the composite container 10A becomes difficult to hold due to being too cold or too hot. As such a material, foamed polyurethane, polystyrene, PE (polyethylene), PP (polypropylene), phenol resin, polyvinyl chloride, urea resin, silicone, polyimide, melamine resin and the like can be considered. It is preferable to mix hollow particles with the resin material containing these resins. The average particle size of the hollow particles is preferably 1 to 200 μm, more preferably 5 to 80 μm. The "average particle size" means a volume average particle size, and is measured by a known method using a particle size distribution / particle size distribution measuring device (for example, Nanotrack particle size distribution measuring device, manufactured by Nikkiso Co., Ltd.). can do. Further, the hollow particles may be organic hollow particles composed of resin or the like, or inorganic hollow particles composed of glass or the like, but are organic because of their excellent dispersibility. Hollow particles are preferred. Examples of the resin constituting the organic hollow particles include a styrene resin such as a crosslinked styrene-acrylic resin, a (meth) acrylic resin such as acrylonitrile-acrylic resin, a phenol resin, a fluorine resin, a polyamide resin, and a polyimide. Examples thereof include based resins, polycarbonate resins, and polyether resins. In addition, Low Pay HP-1055, Low Pay HP-91, Low Pay OP-84J, Low Pay Ultra, Low Pay SE, Low Pay ST (manufactured by Roam and Hearth Co., Ltd.), Nipole MH-5055 (manufactured by Nippon Zeon Co., Ltd.), SX8782 , SX866 (manufactured by JSR Corporation) and other commercially available hollow particles can also be used. The content of the hollow particles is preferably 0.01 to 50 parts by mass, and more preferably 1 to 20 parts by mass with respect to 100 parts by mass of the resin material contained in the plastic member 40a.

Further, the plastic member 40a may be made of a material that is less slippery than the plastic material constituting the container body 10 (preform 10a). In this case, the user can easily grip the composite container 10A without changing the material of the container body 10. For example, a plastic member 40 may be provided on all or part of the body 20 of the container body 10 to make the body 20 easier to hold.

The plastic member 40a may be pre-printed with a design or printing. In this case, printing may be formed by designing or printing on a plain plastic member 40a by a printing method such as an inkjet method or a gravure printing method. This printing may be applied to the plastic member 40a before being attached to the preform 10a, or may be applied with the plastic member 40a provided on the outside of the preform 10a. Further, the plastic member 40a may be colored in a color such as red, blue, yellow, green, brown, black, or white, and may be transparent or opaque.

Next, the shape of the plastic member 40a will be described.

As shown in FIGS. 3 and 4A, the plastic member 40a has a bottomed cylindrical shape as a whole, and has a cylindrical body portion 41 and a bottom portion 42 connected to the body portion 41. You may. In this case, since the bottom 42 of the plastic member 40a covers the bottom 30a of the preform 10a, in addition to the body 20 of the composite container 10A, the bottom 30 also has various barrier properties against light rays having a wavelength of 400 nm to 500 nm. Functions and characteristics can be added. Examples of such a plastic member 40a include the blow tube and the sheet forming tube described above.

Further, as shown in FIGS. 9 (described later) and 4 (b), the plastic member 40a has a circular tube shape (bottomless cylindrical shape) as a whole, and even if it has a cylindrical body portion 41. good. In this case, as the plastic member 40a, for example, the blow tube, extrusion tube, inflation molding tube, and sheet molding tube described above can be used.

Further, as shown in FIGS. 4 (c) and 4 (d), the plastic member 40a may be manufactured by forming a film into a tubular shape and laminating its ends. In this case, as shown in FIG. 4 (c), the plastic member 40a may be formed in a pipe shape (bottomless cylindrical shape) having a body portion 41, and as shown in FIG. 4 (d). It may be formed in a bottomed cylinder shape by sticking the bottom portions 42 together.

Next, the manufacturing method (blow molding method) of the composite container 10A according to the present embodiment will be described with reference to FIGS. 5A to 5F.

First, a preform 10a made of a plastic material is prepared (see FIG. 5A). In this case, for example, a preform 10a may be produced by an injection molding method using an injection molding machine (not shown). The preform 10a has a mouth portion 11a, a barrel portion 20a having a diameter _{d 1} is 25Mm～200mm, a bottom 30a of a substantially hemispherical shape.

Next, the plastic member 40a is prepared. In this case, the plastic member 40a has a bottomed cylindrical shape as a whole, and has a cylindrical body portion 41 and a bottom portion 42 connected to the body portion 41.

Next, by providing the plastic member 40a on the outside of the preform 10a, a composite preform 70 having the preform 10a and the plastic member 40a in close contact with the outside of the preform 10a is produced (FIG. 5 (FIG. 5). b) See).

In this case, a plastic member 40a having an inner diameter equal to or slightly smaller than the outer diameter of the preform 10a may be pushed into the preform 10a so as to be brought into close contact with the outer surface of the preform 10a. Alternatively, as will be described later, a heat-shrinkable plastic member 40a is provided on the outer surface of the preform 10a, and the plastic member 40a is heat-shrinked by heating to 50 ° C. to 100 ° C. to shrink the outer surface of the preform 10a. It may be in close contact with.

In this way, a series of steps for producing the composite preform 70 by bringing the plastic member 40a into close contact with the outside of the preform 10a in advance to prepare the composite preform 70 (FIGS. 5A to 5B). )) And a series of steps (FIGS. 5 (c) to (f)) for producing the composite container 10A by blow molding can be carried out at different places (factory or the like).

Next, the composite preform 70 is heated by the heating device 51 (see FIG. 5C). At this time, the composite preform 70 is uniformly heated in the circumferential direction by the heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a and the plastic member 40a in this heating step may be, for example, 90 ° C to 130 ° C.

Subsequently, the composite preform 70 heated by the heating device 51 is sent to the blow molding die 50 (see FIG. 5D).

The composite container 10A is molded using the blow molding die 50. In this case, the blow molding die 50 includes a pair of body molds 50a and 50b that are separated from each other, and a bottom mold 50c (see FIG. 5D). In FIG. 5D, the pair of body molds 50a and 50b are open to each other, and the bottom mold 50c is raised upward. In this state, the composite preform 70 is inserted between the pair of body molds 50a and 50b.

Next, as shown in FIG. 5 (e), after the bottom mold 50c is lowered, the pair of body molds 50a and 50b are closed and sealed by the pair of body molds 50a and 50b and the bottom mold 50c. The blow-molded mold 50 is constructed.

Next, air is press-fitted into the preform 10a, and biaxial stretch blow molding is performed on the composite preform 70.

As a result, the container body 10 can be obtained from the preform 10a in the blow molding die 50. During this time, the body molds 50a and 50b are heated to 30 ° C. to 80 ° C., and the bottom mold 50c is cooled to 5 ° C. to 25 ° C. At this time, in the blow molding die 50, the preform 10a of the composite preform 70 and the plastic member 40a are integrally expanded. As a result, the preform 10a and the plastic member 40a are integrally shaped into a shape corresponding to the inner surface of the blow molding die 50.

In this way, the composite container 10A including the container body 10 and the plastic member 40 provided on the outer surface of the container body 10 is obtained.

At the time of this blow molding, the lateral stretching ratio of the preform 10a with respect to the container body 10 is 3.5 times or less, preferably 3 times or less. As described above, by suppressing the lateral stretching ratio at the time of blow molding to 3.5 times or less, it is possible to prevent a problem that the plastic member 40a is stretched and broken. On the other hand, the longitudinal stretching ratio of the preform 10a with respect to the container body 10 is preferably 3 times or less.

Next, as shown in FIG. 5 (f), the pair of body molds 50a and 50b and the bottom mold 50c are separated from each other, and the composite container 10A is taken out from the blow molding mold 50.

Modification Example of Manufacturing Method of Composite Container Next, a modification of the manufacturing method (blow molding method) of the composite container 10A according to the present embodiment will be described with reference to FIGS. 6A to 6F. In the modified examples shown in FIGS. 6 (a) to 6 (g), the plastic member (outer contracting member) 40a has an action of contracting with respect to the preform 10a, and the other configurations are shown in FIG. It is substantially the same as the form shown in (f). In FIGS. 6A to 6F, the same parts as those in FIGS. 5A to 5F are designated by the same reference numerals, and detailed description thereof will be omitted.

First, a preform 10a made of a plastic material is prepared (see FIG. 6A).

Next, a plastic member (outer contraction member) 40a is provided on the outside of the preform 10a (see FIG. 6B). In this case, the plastic member (outer contracting member) 40a has a bottomed cylindrical shape as a whole, and has a cylindrical body portion 41 and a bottom portion 42 connected to the body portion 41. The plastic member (outer contraction member) 40a is mounted so as to cover the entire body portion 20a except for the portion corresponding to the neck portion 13 of the container body 10 and the entire bottom portion 30a.

Next, the preform 10a and the plastic member (outer contraction member) 40a are heated by the heating device 51 (see FIG. 6C). At this time, the preform 10a and the plastic member (outer contraction member) 40a are uniformly heated in the circumferential direction by the heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a and the plastic member (outer shrinking member) 40a in this heating step may be, for example, 90 ° C to 130 ° C.

By heating the plastic member (outer shrinking member) 40a in this way, the plastic member (outer shrinking member) 40a is thermally shrunk and adheres to the outside of the preform 10a (see FIG. 6C). .. When the plastic member (outer shrinking member) 40a itself has shrinkage, the plastic member is provided at the time when the plastic member (outer shrinking member) 40a is provided on the outside of the preform 10a (see FIG. 6B). The (outer shrinking member) 40a may be in close contact with the outside of the preform 10a.

Subsequently, the preform 10a and the plastic member (outer shrinking member) 40a heated by the heating device 51 are sent to the blow molding die 50 (see FIG. 6D). In this case, heating for heat-shrinking the plastic member (outer shrinking member) 40a and heating for blow-molding the preform 10a can be performed in the same process.

The preform 10a and the plastic member (outer contraction member) 40a are molded by using the blow molding die 50, and together with the container body 10 in substantially the same manner as in the cases of FIGS. 5A to 5F described above. , A composite container 10A including a plastic member (outer contraction member) 40 provided on the outer surface of the container body 10 can be obtained (see FIGS. 6 (d) to 6 (f)). At this time, the lateral stretching ratio of the preform 10a with respect to the container body 10 is 3.5 times or less, which prevents the plastic member 40a from being stretched and broken.

Next, another modification of the method for manufacturing the composite container 10A (blow molding method) according to the present embodiment will be described with reference to FIGS. 7 (a) to 7 (g). In the modified examples shown in FIGS. 7 (a) to 7 (g), the plastic member (outer contraction member) 40a has an action of contracting with respect to the preform 10a, and the preform 10a and the plastic member (outer contraction member) 40a Is heated in two stages, and the other configurations are substantially the same as the forms shown in FIGS. 5 (a) to 5 (f). In FIGS. 7 (a) to 7 (g), the same parts as those in FIGS. 5 (a) to 5 (f) are designated by the same reference numerals, and detailed description thereof will be omitted.

First, a preform 10a made of a plastic material is prepared (see FIG. 7A).

Next, a plastic member (outer contraction member) 40a is provided on the outside of the preform 10a (see FIG. 7B).

Next, the preform 10a and the plastic member (outer shrinking member) 40a are heated by the first heating device 55 (see FIG. 7C). At this time, the heating temperature of the preform 10a and the plastic member (outer contraction member) 40a may be, for example, 50 ° C. to 100 ° C.

When the plastic member (outer shrinking member) 40a is heated, the plastic member (outer shrinking member) 40a is thermally shrunk and comes into close contact with the outside of the preform 10a. As a result, a composite preform 70 having the preform 10a and a plastic member (outer shrinking member) 40a in close contact with the outside of the preform 10a can be obtained (see FIG. 7C).

In this way, the composite preform 70 is produced by heat-adhering the plastic member (outer contraction member) 40a to the outside of the preform 10a in advance using the first heating device 55 to prepare the composite preform 70. (FIGS. 7 (a) to (c)) and a series of steps (FIGS. 7 (d) to (g)) for producing the composite container 10A by blow molding are performed at different locations (factory, etc.). ) Will be possible.

Next, the composite preform 70 is heated by the second heating device 51 (see FIG. 7D). At this time, the composite preform 70 is uniformly heated in the circumferential direction by the second heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a and the plastic member (outer shrinking member) 40a in this heating step may be, for example, 90 ° C to 130 ° C.

Subsequently, the composite preform 70 heated by the second heating device 51 is sent to the blow molding die 50 (see FIG. 7E).

The composite preform 70 is molded using the blow molding die 50, and is provided on the container body 10 and the outer surface of the container body 10 in substantially the same manner as in the cases of FIGS. 5A to 5F described above. A composite container 10A provided with a plastic member (outer contraction member) 40 is obtained (see FIGS. 7 (e) to 7 (g)). At this time, the lateral stretching ratio of the preform 10a with respect to the container body 10 is 3.5 times or less, which prevents the plastic member 40a from being stretched and broken.

As described above, according to the present embodiment, the preform 10a of the composite preform 70 and the plastic member 40a are integrated by performing blow molding on the composite preform 70 in the blow molding mold 50. To prepare a composite container 10A having a container body 10 and a plastic member 40. As a result, the preform 10a (container body 10) and the plastic member 40a (plastic member 40) can be made of separate members. Therefore, various functions and characteristics can be freely imparted to the composite container 10A by appropriately selecting the type and shape of the plastic member 40.

Further, according to the present embodiment, when the composite container 10A is manufactured by blow molding, the lateral stretching ratio of the preform 10a with respect to the container body 10 is set to 3.5 times or less. This prevents the plastic member 40a from being stretched and broken during blow molding. As a result, the composite container 10A to which various functions and characteristics such as gas barrier properties are imparted can be produced with high quality.

In particular, since it is not necessary to change the shape of the blow molding die 50, it is possible to mold the composite container 10A including the container body 10 and the plastic member 40 by using the conventional blow molding die as it is. ..

Further, according to the present embodiment, when the composite container 10A is manufactured, a general blow molding apparatus can be used as it is, so that it becomes necessary to prepare a new molding facility for manufacturing the composite container 10A. Absent. Further, since the plastic member 40a is provided on the outside of the preform 10a, it is not necessary to prepare a new molding facility for molding the preform 10a.

Modification Example of Composite Container and Composite Preform Next, a modification of the present embodiment will be described with reference to FIGS. 8 and 9.

The modified examples shown in FIGS. 8 and 9 do not have a body and a bottom as the plastic member 40a, but use a cylindrical plastic member 40a.

In the composite container 10A shown in FIG. 8, the plastic member 40 extends from the shoulder portion 12 of the container body 10 to the lower portion of the body portion 20, but does not reach the bottom portion 30. Further, in the composite preform 70 shown in FIG. 9, the plastic member 40a is in close contact so as to cover only the body portion 20a of the preform 10a, and more specifically, the neck portion 13 of the container body 10 of the body portion 20a. It covers the area excluding the portion 13a corresponding to the portion 13a and the portion corresponding to the lower portion of the body portion 20a.

In FIGS. 8 and 9, other configurations are substantially the same as the embodiments shown in FIGS. 1 to 7. In the modified examples shown in FIGS. 8 and 9, the same parts as those of the embodiments shown in FIGS. 1 to 7 are designated by the same reference numerals, and detailed description thereof will be omitted. Further, since the configuration and manufacturing method of the composite container 10A and the configuration and manufacturing method of the composite preform 70 are substantially the same as those of the embodiments shown in FIGS. 1 to 7, detailed description thereof will be omitted. Further, in FIGS. 8 and 9, those having a function of shrinking the plastic member 40 with respect to the preform 10a may be used.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. 10 to 17. 10 to 17 are views showing a second embodiment of the present invention. In FIGS. 10 to 17, the same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

First, the outline of the composite container according to the present embodiment will be described with reference to FIGS. 10 and 11.

As will be described later, the composite container 10A shown in FIGS. 10 and 11 is formed into a composite preform 70 (see FIG. 12) including a preform 10a, an inner label member 60a, and a plastic member 40a by using a blow molding die 50. On the other hand, it is obtained by integrally expanding the preform 10a, the inner label member 60a, and the plastic member 40a of the composite preform 70 by performing biaxial stretch blow molding.

Such a composite container 10A is provided in close contact with the container body 10 made of a plastic material located inside, the inner label member 60 provided in close contact with the outside of the container body 10, and the outer side of the inner label member 60. It is provided with a plastic member 40.

Of these, the inner label member 60 is in close contact with the outer surface of the container body 10 in a thinly extended state, and is in close contact with the container body 10 so as not to easily move or rotate.

Further, the plastic member 40 is in close contact with the outer surface of the container body 10 and the outer surface of the inner label member 60 in a thinly extended state, and is in close contact with the container body 10 so as not to easily move or rotate. There is.

It is considered that at least a part of the plastic member 40 is translucent or transparent, and in this case, the inner label member 60 can be visually recognized from the outside through the translucent or transparent portion. The plastic member 40 may be translucent or transparent as a whole, or may have an opaque portion and a translucent or transparent portion (for example, a window portion).

Next, the inner label member 60 will be described. The inner label member 60 (60a) is provided so as to surround the outside of the preform 10a as described later, and is obtained by biaxially stretching blow molding integrally with the preform 10a and the plastic member 40a. It is a thing.

The inner label member 60 is attached to the outer surface of the container body 10 without being adhered, and is in close contact with the container body 10 so as not to move or rotate. The inner label member 60 is thinly stretched on the outer surface of the container body 10 to cover the container body 10. As shown in FIG. 11, the inner label member 60 is provided over the entire circumferential direction so as to surround the container body 10, and has a substantially circular horizontal cross section.

In this case, the inner label member 60 is provided so as to cover the shoulder portion 12, the body portion 20, and the bottom portion 30 of the container body 10, excluding the mouth portion 11 and the neck portion 13. As a result, desired characters, images, and the like can be added to the shoulder portion 12, the body portion 20, and the bottom portion 30 of the container body 10, and the composite container 10A can be decorated and information can be displayed.

The inner label member 60 may be provided in the entire area or a part of the container body 10 other than the mouth portion 11 and the neck portion 13. For example, the inner label member 60 may be provided so as to cover the entire body portion 20 and bottom portion 30 of the container body 10 except for the mouth portion 11, the neck portion 13 and the shoulder portion 12. Further, the number of inner label members 60 is not limited to one, and a plurality of inner label members 60 may be provided. The inner label member 60 may be provided in the same area as the plastic member 40, or may be provided in a narrower area than the plastic member 40. In the latter case, the inner label member 60 is preferably completely covered by the plastic member 40.

The thickness of the inner label member 60 is not limited to this, but can be, for example, about 1 μm to 100 μm when attached to the container body 10.

In addition, the configurations of the container body 10 and the plastic member 40 are substantially the same as those of the first embodiment described above, and thus detailed description thereof will be omitted here.

Next, the configuration of the composite preform according to the present embodiment will be described with reference to FIG.

As shown in FIG. 12, the composite preform 70 includes a preform 10a made of a plastic material, a bottomed cylindrical inner label member 60a provided in close contact with the outer side of the preform 10a, and an inner label member 60a. It is provided with a bottomed cylindrical plastic member 40a provided in close contact with the outside.

The inner label member 60a is in close contact with the outer surface of the preform 10a so that it does not easily move or rotate with respect to the preform 10a, or is in close contact with the preform 10a so as not to fall under its own weight. The inner label member 60a is provided over the entire circumferential direction so as to surround the preform 10a, and has a substantially circular horizontal cross section.

The inner label member 60a may be pre-designed or printed. For example, in addition to the design, product name, and the like, character information such as the name of the content liquid, the manufacturer, and the name of the raw material may be described. In this case, it is possible to display an image or characters on the composite container 10A without separately attaching a label or the like to the container body 10 after blow molding. For example, the inner label member 60a may be provided on all or part of the body portion 20a of the preform 10a so that an image or characters can be displayed on the body portion 20 of the container body 10 after molding. This eliminates the need for a step of attaching a label using a labeler after sealing the container, so that the manufacturing cost can be suppressed and the yield can be prevented from being lowered.

As such an inner label member 60a, an unstretched film such as a polyester resin, a polyamide resin, a polyaramid resin, a polypropylene resin, a polycarbonate resin, a polyacetal resin, or a fluorine resin can be used. The inner label member 60a may be made of the same material as the container body 10 (preform 10a) and / or the plastic member 40a, or may be made of a different material.

On the other hand, the plastic member 40a is attached to the outer surface of the inner label member 60a without being adhered to the preform 10a so as not to move or rotate, or to the extent that it does not fall due to its own weight. Has been done.

The inner label member 60a and the plastic member 40a may be provided in the entire area or a part of the area other than the mouth portion 11a. For example, the inner label member 60a and the plastic member 40a may be provided so as to cover the entire body portion 20a and the bottom portion 30a except for the mouth portion 11a. Further, the inner label member 60a and the plastic member 40a are not limited to one each, and a plurality of inner label members 60a may be provided. For example, two inner label members 60a and a plastic member 40a may be provided at two locations on the outer side of the body portion 20a, respectively.

In addition, since the configurations of the preform 10a and the plastic member 40a are substantially the same as those of the above-described first embodiment, detailed description thereof will be omitted here.

Next, the manufacturing method (blow molding method) of the composite container 10A according to the present embodiment will be described with reference to FIGS. 13 (a) to 13 (f).

First, a preform 10a made of a plastic material is prepared (see FIG. 13A). The preform 10a has a mouth portion 11a, a body portion 20a having a diameter of 25 mm to 100 mm, and a substantially hemispherical bottom portion 30a.

Next, the inner label member 60a is provided on the outer side of the preform 10a, and the plastic member 40a is provided on the outer side of the inner label member 60a. As a result, a composite preform 70 having a preform 10a, an inner label member 60a adhered to the outside of the preform 10a, and a plastic member 40a adhered to the outside of the inner label member 60a is produced (FIG. 13). See (b)). In this case, the inner label member 60a has a bottomed cylindrical shape as a whole, and has a cylindrical body portion 61 and a bottom portion 62 connected to the body portion 61.

At this time, even if the inner label member 60a and the plastic member 40a having the same or slightly smaller inner diameter as the outer diameter of the preform 10a are pushed against the preform 10a, they are brought into close contact with the outer surface of the preform 10a. good. Alternatively, a heat-shrinkable inner label member 60a and a plastic member 40a are provided on the outer surface of the preform 10a, and the inner label member 60a and the plastic member 40a are heat-shrinked by heating to 50 ° C. to 100 ° C. It may be brought into close contact with the outer surface of the preform 10a.

Further, a plastic member 40a may be provided in advance around the inner label member 60a, and the inner label member 60a and the plastic member 40a may be integrally mounted on the outside of the preform 10a. Alternatively, the inner label member 60a may be provided on the outer side of the preform 10a, and then the plastic member 40a may be provided on the outer side of the inner label member 60a.

In this way, a series of steps for producing the composite preform 70 by bringing the plastic member 40a into close contact with the outside of the preform 10a and the inner label member 60a in advance to prepare the composite preform 70 (FIG. 13 (FIG. 13). It becomes possible to carry out a series of steps (FIGS. 13 (d) to (f)) for producing the composite container 10A by blow molding at different places (factory or the like).

Next, the composite preform 70 is heated by the heating device 51 (see FIG. 13C).

Subsequently, the composite preform 70 heated by the heating device 51 is sent to the blow molding die 50. The composite container 10A is molded using the blow molding die 50, and is provided on the container body 10 and the outer surface of the container body 10 in substantially the same manner as in the case of the first embodiment described above. A composite container 10A including the 60 and a plastic member 40 provided on the outside of the inner label member 60 is obtained (see FIGS. 13 (d)-(f)). At this time, the lateral stretching ratio of the preform 10a with respect to the container body 10 is 3.5 times or less, which prevents the plastic member 40a and the inner label member 60a from being stretched and broken. ..

In addition, the manufacturing method (blow molding method) of the composite container 10A according to the present embodiment is substantially the same as that of the first embodiment described above, and thus detailed description thereof will be omitted here.

Modification Example of Blow Molding Method FIGS. 14 (a) to 14 (f) and FIGS. 15 (a) to 15 (g) are diagrams showing a modification of the method for manufacturing the composite container 10A (blow molding method) according to the present embodiment, respectively. Is. In FIGS. 14 (a) to 14 (f) and FIGS. 15 (a) to 15 (g), the same parts as those in FIGS. 1 to 13 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the modification shown in FIGS. 14A to 14F, the inner label member 60 is provided on the outside of the preform 10a, and the plastic member (outer shrinkage member) 40a is provided on the outside of the inner label member 60. The other configurations are substantially the same as the forms shown in FIGS. 6A to 6F.

In the modification shown in FIGS. 15 (a) to 15 (g), the inner label member 60 is provided on the outer side of the preform 10a, and the plastic member (outer shrinkage member) 40a is provided on the outer side of the inner label member 60. The other configurations are substantially the same as the forms shown in FIGS. 7 (a) to 7 (g).

Modification Example of Composite Container and Composite Preform Next, a modification of the present embodiment will be described with reference to FIGS. 16 and 17.

The modified examples shown in FIGS. 16 and 17 do not have a body and a bottom as the inner label member 60a and the plastic member 40a, but use the cylindrical inner label member 60a and the plastic member 40a. .. Other configurations are substantially the same as those of the embodiments shown in FIGS. 10 to 13. In the modified examples shown in FIGS. 16 and 17, the same parts as those of the embodiments shown in FIGS. 10 to 13 are designated by the same reference numerals, and detailed description thereof will be omitted. Further, the method for producing the composite container 10A and the method for manufacturing the composite preform 70 are substantially the same as those of the embodiments shown in FIGS. 10 to 13, so detailed description thereof will be omitted.

Next, a specific embodiment of the present embodiment will be described.

First, the following two types of preforms (Example 1 and Comparative Example 1) were produced by injection molding.

(Example 1)
A PET preform 10a (Example 1) according to this embodiment was produced. In this preform 10a (Example 1), the diameter d ₁ of the body portion 20a is 26 mm, the height h ₁ from the lower part of the flange portion 17 to the lowest point of the bottom portion 30a is 76 mm, and the height h of the mouth portion 11a. ₂ was set to 21 mm, and the maximum thickness t ₁ of the preform 10a in the body portion 20a was set to 3.5 mm.

(Comparative Example 1)
A PET preform (Comparative Example 1) having a conventional general shape was produced. In this preform (Comparative Example 1), the diameter d ₁ of the body portion is 22 mm, the height h ₁ from the lower part of the flange portion to the lowest point of the bottom portion is 80 mm, and the height h ₂ of the mouth portion is 21 mm. The maximum thickness t _{1 of the} preform in the body was 3.8 mm.

Next, a plastic member 40a having an inner diameter corresponding to each of these two types of preforms (Example 1 and Comparative Example 1) is attached, and the same method as shown in FIGS. 5A to 5F is performed. By biaxial stretching blow molding, a composite container 10A having a container body 10 and a plastic member 40 was produced. As the plastic member 40a, a polyethylene direct blow molded tube was used, and the thickness t ₂ thereof was 400 μm.

In the container body 10 of the composite container 10A, the height H ₁ from the lower side of the flange portion 17 to the ground contact portion was 185 mm, and the maximum diameter D ₁ in the body portion 20 of the container body 10 was 90 mm. The full filling capacity of the container body 10 was 1000 ml.

As a result, the draw ratio of the preform 10a of Example 1 was 3.46 times, and the plastic member 40a did not break. On the other hand, the draw ratio of the preform of Comparative Example 1 was 4.09 times, and the plastic member 40a was broken.

10 Container body 10A Composite container 10a Preform 11, 11a Mouth 12 Shoulder 13 Neck 14 Thread 17 Flange 20, 20a Body 30, 30a Bottom 40, 40a Plastic member 41 Body 42 Bottom 50 Blow molding die 60, 60a Inner label member 61 Body 62 Bottom 70 Composite preform

Claims (6)

In the method of manufacturing a composite container
The process of preparing a preform made of plastic material while having a mouth, a body, and a bottom,
A step of providing a plastic member on the outside of the preform and heat-shrinking the plastic member to bring it into close contact with the outer surface of the preform.
By performing blow molding on the preform and the plastic member using a blow molding die, the preform and the plastic member are integrally expanded, and the container body corresponding to the preform and the container body and the said. A step of producing a composite container having a plastic member provided on the outside of the container body in close contact with each other so as to be non-adhesive and removable.
In the step of producing the composite container, the lateral stretching ratio of the preform to the container body is set to 3.5 times or less .
A method for manufacturing a composite container, wherein the plastic member after blow molding has a cutting line for peeling and removing from the container body . The method for manufacturing a composite container according to claim 1, wherein the maximum thickness of the body portion of the preform is 2 mm to 10 mm. The method for manufacturing a composite container according to claim 1 or 2, wherein the maximum thickness of the plastic member before blow molding is 0.1 mm to 2 mm. A composite preform characterized by being used in the method for producing a composite container according to claim 1. The composite preform according to claim 4, wherein the maximum thickness of the body portion of the preform is 2 mm to 10 mm. The composite preform according to claim 4 or 5, wherein the maximum thickness of the plastic member is 0.1 mm to 2 mm.

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